cannot find definition Class on node <some node> (when using a specific environment)

Hello,

We've recently moved to a new HA puppet environment using SRV records and 2 puppet masters to server catalogs (and another separate server to serve CA requests).
All puppet masters are running with Apache + passenger.
The 2 masters mount the same Netapp share as their /etc/puppet directory so the configuration applies to both.

We have a few environments, the mainly used are the main environment and the "deployments" environment we're using to deploy new versions of our code.

Here's the configuration:

[deployments]

manifest = /etc/puppet/deployments/site.pp

modulepath = /etc/puppet/rndmodules:/etc/puppet/submodules:/etc/puppet/opmodules

pluginsync=true

filetimeout = 10

[master]

	ca = false

	modulepath = /etc/puppet/testmodules/:/etc/puppet/rndmodules:/etc/puppet/opmodules:/etc/puppet/submodules

	ssl_client_header = SSL_CLIENT_S_DN

	ssl_client_verify_header = SSL_CLIENT_VERIFY

	filetimeout = 10

After moving to the new HA solution described above we started getting the following error intermittently when running with the "deployments" environment:

Error: Could not retrieve catalog from remote server: Error 400 on SERVER: Cannot find definition Class on node <current node>.

it sometimes even work only after the fifth attempt.

This never happened before when we were using a single puppet master to server both catalogs and CA (Without SRV records of course)

I saw a couple of threads describing this error, but it didn't lead me anywhere.
I've added debug to the rack config.ru but it doesn't give any more details.

I also tried to change the SRV priorities so that the agent's work with a single master, but there was no change.

Where could the issue be? is it a bug? Can the Netapp share between the masters cause any of these issues? Is it the SRV records solution causing issues?

Please assist.
Thanks